This veteran manufacturer offers a classic range of propellers for Glow Fuel Powered Aircraft. Anywhere from 7" all the way up to mammoth 16" in diameter. The boss is precision drilled to 6mm, so fitting most manufacturers Glow Fuel Engines. Consult the engine maker's manual to choose the optimum propeller. Graupner also supply the CamSpeed and CamSlim ranges of tractor prop for use with Electric Powered Aircraft, these offer terrific thrust capability, so if Sports Electric Models are your thing these props will give you superb performance.